Methods and systems of the above kind are primarily used in the area of road traffic.
The situation and the trend in road traffic are characterized in that more motor vehicles are licensed from year to year than are taken out of service. This leads to an ever greater traffic density which, in turn, imposes higher requirements on the operator of a motor vehicle.
The accident statistics show an ever increasing number of traffic accidents with significant human loss as well as health and material damage even though the severe and fatal injuries become less as a consequence of improved safety comfort of the vehicles.
From the state of the art, it can be seen that attempts are made to facilitate for the vehicle operator the realization of risk elements which hinder road traffic. Accordingly, a series of technical apparatus have become known wherein the application of the most different sensors is shown for the detection of obstacles in the vicinity of the motor vehicle and other dangers for traffic safety. Sensors are described, inter alia, in U.S. Pat. Nos. 6,926,374 and 6,054,936 and German patent publications 101 03 767 A1 and 195 01 950 A1 which not only detect individual obstructions but look at the entire vicinity of the vehicle and differentiate between stationary and mobile obstacles on the one hand and persons, which are moving, on the other hand, and which are to be avoided.
These sensors include also detectors having photonic mixer diodes as they are described in U.S. Pat. No 6,777,659 and German patent publication 199 16 123.
A universal system of communication, information and navigation is disclosed in German patent publication 101 63 990. This system uses mobile parts, central servers and the most various methods of satellite navigation and of mobile communications in order to announce and to avoid multiple dangers.
An arrangement for controlling the speed of a motor vehicle is described in German patent publication 41 23 110. This arrangement determines the factors which influence vehicle speed (such as driver command, distance to a forward vehicle, traction of the roadway and speed or the like) and, from these factors, the arrangement determines an individually permissible maximimum speed.
German patent publication 197 00 353 discloses an arrangement for diagnosing, controlling, transmitting and storing safety relevant system state variables. This arrangement evaluates and qualifies sensor-determined state variables and generates control operations when there are safety-critical deviations to a desired state.
In addition, German patent publication 43 38 244 describes a danger-avoidance system for a vehicle wherein the state of the motor vehicle, the vicinity of the roadway and the operator are monitored. From the data obtained in this way, the danger potential is evaluated and a corresponding control signal is generated when there is a specific danger situation.
Finally, German patent publication 197 45 166 describes a method for monitoring the safety of a motor vehicle wherein first the instantaneous position is determined from a digitally stored map and an intended roadway is selected. Thereafter, all dangerous locations, which are along this roadway, are localized and an automatic braking is triggered when the instantaneous speed exceeds a critical speed for the particular danger location and the instantaneous distance to this danger site.
A method for controlling the speed of a motor vehicle with respect to risk is described in the article entitled “How far can the computer replace the Driver in Automatic Driving”, Automotive Engineer, GB, Vol. 20, No. 5, Oct. 1, 1995, pages 18 to 20. In this method, the instantaneous speed is measured and risk elements are determined during travel from which an integral risk potential is computed. This integral risk potential then functions as the basis for a change of the speed. This method, however, does not consider the interrelationships of element quantity and speed moderated specific dangers of the risk elements as the two components of the integral risk potential and is therefore unsuitable for an effective application.
German patent publication 197 00 353 describes an arrangement for diagnosing, controlling, transmitting and storing safety-relevant system state quantities of a motor vehicle. In this method, the following are utilized: sensors for detecting risk elements, a display and a risk decoder for processing information quantities. For this purpose, the risk decoder is also connected to a speed sensor. However, this arrangement too does not consider or considers only inadequately the two components of the risk potential and therefore functions inaccurately.
All of the above methods and arrangements proceed from the consideration that operating disturbances of modern vehicle technology (insofar as they can not be independently controlled) are automatically displayed so that the risk potential is dependent decisively upon perception losses of the driver of the motor vehicle as to the permanent and temporary risk elements of the traffic environment. This consideration corresponds to the basic recognition of the perception theory which states that the vehicle driver perceives approximately 90% of his information visually of which 40 to 50% are only incompletely or defectively interpreted under controlled conditions. Correspondingly, all known technical arrangements are directed to the improvement of the information for the operator of the motor vehicle.
Recent investigations show, however, that the perception losses and therefore also the risk potential increase not only with the number of risk elements of the external milieu and therefore with the quantity of information. The risk potential increases with the specific dangerousness of the permanent and temporary elements of the external milieu which, in turn, are dependent upon the speed and upon the typical traffic situation. Here, however, not only the speed itself is significant. Traffic modules and town-conditions modules of the infrastructure also have a considerable influence. Accordingly, exceeding the permissible speed of 30 km/h can be associated with consequences to the same extent as exceeding a permissible speed of 100 km/h.
This realization is not taken into account by any of the known technical systems so that these technical systems are not suitable to significantly reduce the occurrence of traffic accidents.